Bone marrow ectopic expression of a non-coding RNA in childhood T-cell acute lymphoblastic leukemia with a novel t(2;11)(q11.2;p15.1) translocation.
Chromosomal translocations play a crucial role in tumorigenesis, often resulting in the formation of chimeric genes or in gene deregulation through position effects. T-cell acute lymphoblastic leukemia (T-ALL) is associated with a large number of such rearrangements. We report the ectopic expression of the 3' portion of EST DA926692 in the bone marrow of a childhood T-ALL case showing a t(2;11)(q11.2;p15.1) translocation as the sole chromosome abnormality. The breakpoints, defined at the sequence level, mapped within HPS5 (Hermansky Pudlak syndrome 5) intron 1 at 11p15.1, and DA926692 exon 2 at 2q11.2. The translocation was accompanied by a submicroscopic inversion that brought the two genes into the same transcriptional orientation. No chimeric trancript was detected. Interestingly, Real-Time Quantitative (RQ)-PCR detected, in the patient's bone marrow, expression of a 173 bp product corresponding to the 3' portion of DA926692. Samples from four T-ALL cases with a normal karyotype and normal bone marrow used as controls were negative. It might be speculated that the juxtaposition of this genomic segment to the CpG island located upstream HPS5 activated DA92669 expression. RQ-PCR analysis showed expression positivity in 6 of 23 human tissues examined. Bioinformatic analysis excluded that this small non-coding RNA is a precursor of micro-RNA, although it is conceivable that it has a different, yet unknown, functional role. To the best of our knowledge, this is the first report, in cancer, of the activation of a small non-coding RNA as a result of a chromosomal translocation.
Guastadisegni
Maria Corsignano
MC
Department of Genetics and Microbiology, University of Bari, Bari, Italy. m.guastadisegni@biologia.uniba.it
Lonoce
Angelo
A
Impera
Luciana
L
Albano
Francesco
F
D'Addabbo
Pietro
P
Caruso
Sebastiano
S
Vasta
Isabella
I
Panagopoulos
Ioannis
I
Leszl
Anna
A
Basso
Giuseppe
G
Rocchi
Mariano
M
Storlazzi
Clelia Tiziana
CT
D000293:Adolescent; D001483:Base Sequence; D001853:Bone Marrow / Q000378:metabolism*; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics*; D002889:Chromosomes, Human, Pair 2 / Q000235:genetics*; D015870:Gene Expression; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008969:Molecular Sequence Data; D054218:Precursor T-Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics*; D022661:RNA, Untranslated / Q000235:genetics* / Q000378:metabolism; D014178:Translocation, Genetic
D022661:RNA, Untranslated